This invention relates to polyphosphazene copolymers containing repeating ##STR2## units in the polymer chain in which tetraalkyl orthosilicate substituents and substituted and unsubstituted alkoxy, aryloxy, amino or mercapto substituents are attached to the phosphorus atom and a process for the manufacture thereof. More particularly, the invention relates to polyphosphazene copolymers containing substituents derived from tetraalkyl orthosilicate and substituted and unsubstituted aliphatic and aromatic alcohols, amino compounds and mercaptan compounds, and a simplified process for the manufacture thereof.
Polyphosphazene polymers containing repeating ##STR3## units in which various alkoxy, substituted alkoxy, aryloxy and substituted aryloxy groups are attached to the phosphorus atom and their method of preparation are described in the prior art as illustrated in the publication "Phosphorus-Nitrogen Compounds", Academic Press, New York, N.Y. 1972 by H. R. Allcock and "Poly(Organophosphazenes)", Chemtech, Sept. 19, 1975 by H. R. Allcock and in such U.S. Pat. Nos. as 3,515,688; 3,702,833; and 3,856,712.
However, none of the prior art of which applicants are aware, discloses or suggests polyphosphazene copolymers prepared from a tetraalkyl orthosilicate substituent reacting with a polydichlorophosphazene to give trialkyl silicate attached to the phosphorus atom in the random chain linkage of this invention or the simplified method of preparing such copolymers.